NH TC35D Bad Safety Switch.....But Which One ??

   / NH TC35D Bad Safety Switch.....But Which One ?? #1  

kozak

Platinum Member
Joined
Feb 1, 2004
Messages
629
Location
Forest, Ontario Canada
Tractor
New Holland TC35D c/w FEL, ACCO Allis 1614
Hello all,

Had the tractor out last week to do the horse manure compost run. After I finished turning the compost, I thought I would get off the tractor to do a small task so turned tractor off. When I got back on again & started the tractor...... put it in gear.....tractor shut-down. Oh...oh, that's not common.

So I tried to start again & tractor started right back up......no problemo.....whew......I thought. Took break off (cannot remember if I had a chance to put it in gear) and tractor died again. Ok......this is definitely not good. :(

Put break pedal in & lifted latch to lock in. Checked to ensure gear lever was in neutral. Tried to start.....& bingo....started right up....no hesitation. Pressed in brake pedal to disengage break latch & tractor immediately died. Ok....now I'm thinking that the safety switch for the parking break has failed open. So the next time I start & push in the break pedal, just as the tractor starts dying I quickly lift the break latch & the tractor keeps running. While keeping the latch lifted (break light is lit on dash) I put the tractor in gear & slowly start backing out when the tractor quickly once again dies. :(

It was dark & late & I needed to get the tractor back to the barn. So I kept on with this same routine. (Did'nt have far to go) I was able to start going longer distances & it seemed whenever I hit a small dip.....the tractor died. Must have been about 5 stops & starts over about 5 minutes & I made it to the barn. :)

I figure....ok....should'nt be a big deal, I'll try bypassing the break lever safety switch the following week-end & that should fix it. That is....unless the safety switch is actually triggered off the break pedal / linkages....which would make more sense to me.

Checked the electrical schematic in the User Manual & sure enough you can see the seat safety switch wired in parallel to the neutral gear & parking break safety switches which are then wired to the safety module. This is where my initial assumption I think is wrong. If I can start the tractor, I no longer need either the gear or parking break safety switches to be engaged. (Duh....otherwise I would'nt be going too far)

I started to think about those dips when the tractor died & the way the safety switches are wired & am now thinking it is the seat switch. Just a coincidence that the tractor kept running when I had the parking break lever lifted up. At least I hope that is what it is otherwise......... ??

I am going to try & bypass the seat switch first. If that does'nt work then the break switch.

What do you guys think......ever have something similar ??


Vic
 
   / NH TC35D Bad Safety Switch.....But Which One ?? #3  
I agree with RickB that the seat switch is the culprit. Remember, you can start your tractor out of the seat if it is in neutral, the PTO off, and the parking brake is set. As soon as you change any of those things with a faulty seat switch, the engine will shut down. I think if you change or repair your seat switch, you'll be good to go. For a temporary fix, you can remove the seat switch plug and jumper between the two wires in the plug to simulate a closed seat switch. Mine has been that way from when I bought my tractor, but I would not recommend that to anyone else except as an emergency issue.
 

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   / NH TC35D Bad Safety Switch.....But Which One ?? #4  
Sounds like the seat switch to me too. Like Jinman's, mine is bypassed. You either need to find and fix the switch or wire problem, or eat more and put on some weight to hold the seat down :D
Dave.
 
   / NH TC35D Bad Safety Switch.....But Which One ??
  • Thread Starter
#5  
You guys are right on the mark AGAIN. :)

Did the jumper routine on the seat switch & voila....... tractor is just a hum'in dynamo.

You guys are the Best,

Thanks & Have a G R E A T Holiday Season, ;)

Vic
 

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   / NH TC35D Bad Safety Switch.....But Which One ?? #6  
You guys are right on the mark AGAIN. :)

Did the jumper routine on the seat switch & voila....... tractor is just a hum'in dynamo.


Stand up and take a bow, Vic. . .You can do that now without killin' the engine.;):D
 
   / NH TC35D Bad Safety Switch.....But Which One ?? #7  
I Know this is an old post but I have a similar issue and I have done most everything you guys have suggested and still am with a tractor sitting in the field! here's the skinny: I was driving and stopped to throw a ladder in the bucket. Put the tractor in neutral, set the brake, pto was off, and jumped off. The tractor started to die out so I put my hand on the seat to keep it going. I double checked I wasn't in gear and the brake was set and pto was off. Everything was ok so I let go of the seat and grabbed the ladder. Tractor then shut off and I didn't think much of it. I jumped back on and turned the key on, everything turned on as it should, I turned the key to start it and nothing happened.

So far I have replaced the seat, pto, and neutral safety switches. I replaced the relay's for the safety switches and even the operating safety module. I had the started checked and rebuilt too. Still nothing!!! I keep telling myself I am over looking something but I cannot think of anything else to save my life. All wires appear to be in good shape no bare spots that I can tell of.

Not ready to throw in the towel and call a service tech out to the field but might have to. Thanks in advance!
 
   / NH TC35D Bad Safety Switch.....But Which One ?? #8  
Does the brake have to be set? i.e. is there a switch that checks this and lets the tractor run if out of seat?
 
   / NH TC35D Bad Safety Switch.....But Which One ?? #9  
There is a brake that needs to be set, I did set it and I have replaced that switch too, forgot to mention that. I ever replaced all the fuses under the dash cluster.
 
   / NH TC35D Bad Safety Switch.....But Which One ?? #10  
This winter my NH T2310 would start, but kill whenever I started to go forward. I was ready to install a new seat safety switch, but first, I sprayed some electronics cleaner on the contacts. That did the trick. It has worked ever since. Not sure that is your issue, but is quick and easy to try.
 
 
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